That Prefs-program is so difficult for me to understand, that editing icon by icon in SYS:Prefs/Env-Archive/Sys/Is for me, much easier (but a very slow procedure). Prefs/Deficons seems to be aimed at "rocket scientists"...

Just right-click over the file icon and see what the red word at the top ofthe Context Menu says. If it says "project", it's not recognized as anything specific. If it is recognized, it will say something like "txt","jpeg", etc.

If recognized, then skip to below. If not, then you have face DefIconsPrefs and set up a file type and how it will be recognized. It ischallenging, but if you roam around and look at it's existing settings,you'll get a good idea of how it works. A lot of times, a simple suffixPATTERN match is good enough (that's all lesser systems do).

Once your file type is recognized, then the easiest, direct way I know ofsetting the "Default Tool" for a given file type is to just open WBInfo onthe file, change the program you want to use as a "Default Tool" and thenuse the "Save as default <file type>" menu item.

Easy Peasy!

A few caveats to note:

- if your data file already has an icon file (an .info file) then the settings in that icon will preempt whatever you set for the system Default Tool. You can fix that by opening the WBinfo on that file and using the menu item "Delete icon" to get rid of that file's .info file and then rely on the system Default config.

- If you can, use the APPDIR:<tool name> path instead of a literal path to somewhere on your system. For example, you could call Multiview like this:

APPDIR:Multiview

That lets the system use whatever tool you used wherever you last used it from. It will also avoid some of the problems with tools not being found if you move files/programs between drives, systems, etc.

- After setting/changing the Default Tool, you usually have to close and reopen the WB directory where you data files are to be able to use the new setting.

- DefIcons can sometimes be finnicky about the list order in which the definitions are created. Things at the top of the list take precedence over matches lower in the list.